accidently undefed M_PI.

[[Imported from SVN: r3997]]

io/visual/grape/grape_undefs.hh

@@ -2358,18 +2358,6 @@
   #undef G_UPPER_BOUND
 #endif // G_UPPER_BOUND
 
-#ifdef M_PI
-  #undef M_PI
-#endif // M_PI
-
-#ifdef M_PI_2
-  #undef M_PI_2
-#endif // M_PI_2
-
-#ifdef M_E
-  #undef M_E
-#endif // M_E
-
 #ifdef G_VOID_P_TO_ANY_P
   #undef G_VOID_P_TO_ANY_P
 #endif // G_VOID_P_TO_ANY_P
@@ -2874,10 +2862,6 @@
   #undef G_NOEDGE
 #endif // G_NOEDGE
 
-#ifdef restrict
-  #undef restrict
-#endif // restrict
-
 #ifdef G_MAX_BND_FUNCTIONS
   #undef G_MAX_BND_FUNCTIONS
 #endif // G_MAX_BND_FUNCTIONS